William Windsor (goat)

William Windsor I
Nickname(s)Billy
Born2000 (24–25 years old)
Whipsnade Zoo
Allegiance United Kingdom
BranchBritish Army
Years of service2001–2009
RankLance corporal
Service number25232301
Unit1st Battalion, the Royal Welsh
RetirementWhipsnade Zoo

William "Billy" Windsor I is a cashmere goat who served as a lance corporal in the 1st Battalion, the Royal Welsh, an infantry battalion of the British Army. He served as a lance corporal from 2001 until 2009, except for a three-month period in 2006 when he was demoted to fusilier, after inappropriate behaviour during the Queen's Official Birthday celebrations while deployed on active duty with the battalion on Cyprus. He retired to Whipsnade Zoo in May 2009.

His young replacement is known as William Windsor II.